Rockwell Scale Application Guide
(All regular scales use a 10 kgf minor load)
| Scale Symbol | Indenter | Major Load kgf | Typical Applications of Scales |
| HRA | Brale® Diamond | 60 | Cemented carbides, thin steel and shallow case hardened steel |
| HRB | 1/16" ball | 100 | Copper alloys, soft steels, aluminum alloys, malleable iron |
| HRC | Brale® Diamond | 150 | Steel, hard cast irons, pearlitic malleable iron, titanium, deep case hardened steel and other materials harder than B100 |
| HRD | Brale® Diamond | 100 | Thin steel and medium case hardened steel and pearlitic malleable iron |
| HRE | 1/16" ball | 100 | Cast iron, aluminum and magnesium alloys, bearing metals |
| HRF | 1/16" ball | 60 | Annealed copper alloys, thin soft sheet metals |
| HRG | 1/16" ball | 150 | Phosphor bronze, beryllium copper, malleable irons. Upper limit G92 to avoid possible flattening of ball |
| HRH | 1/8" ball | 60 | Aluminum, zinc, lead |
| HRK HRL HRM HRP HRR HRS HRV |
1/8" ball 1/4" ball 1/4" ball 1/4" ball 1/2" ball 1/2" ball 1/2" ball |
150 60 100 150 60 100 150 |
Bearing metals and other very soft or thin materials, including plastics (See ASTM D785). Use smallest ball and heaviest load that do not give anvil effect. |
| Rockwell superficial scales are used to test materials too thin for the regular scales. Generally Brale® Diamond Indenters are used for hard materials while Ball Indenters are used on soft materials. (All superficial scales use a 3 kgf minor load.) | |||
| HR15N HR30N HR45N |
Brale® Diamond | 15 kg 30 kg 45 kg |
|
| HR15T HR30T HR45T |
1/16" ball | 15 kg 30 kg 45 kg |
|
| HR15W HR30W HR45W |
1/8" ball | 15 kg 30 kg 45 kg |
|
| HR15X HR30X HR45X |
1/4" ball | 15 kg 30 kg 45 kg |
|
| HR15Y HR30Y HR45Y |
1/2" ball | 15 kg 30 kg 45 kg |
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